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Raise Low Input Voltage with 12V Step-Up Voltage Regulator U3V40F12
The 12V Step-Up Voltage Regulator U3V40F12 boosts a lower DC input up to a regulated output, making it useful when your source voltage falls below the level your load needs.
It works well in battery builds, portable electronics, and small robots where input voltage can sag over time.
Important: Choose a regulator based on your full input-voltage range, startup current, thermal limits, and required headroom. Real output current depends on input voltage, airflow, and temperature.
Why you'll love it
- Output: fixed 12V with 4% accuracy
- Input: 1.3V–12V (must start at ≥2.7V ; can run lower after startup)
- Efficiency: typically 85%–95% depending on VIN/load
- Power behavior: power-save mode keeps switching above audible range (>20kHz) for better light-load efficiency
- Protections: over-temperature shutdown, soft-start, output over-voltage protection (~16.5V), and input current limiting
- Actively limits instantaneous input current to 9.5A while boosting (helps protect the regulator)
What you can build
Useful for battery projects, portable devices, LED systems, and electronics that need a higher rail from a lower source voltage.
Compare regulator options
| Model | Topology | Output | Max current |
|---|---|---|---|
| U3V40F12 | Boost | 12 V | — |
| D24V22F12 | Buck | 12 V | 2.2 A |
| D36V28F12 | Buck | 12 V | 2.4 A |
| S13V25F12 | Buck-Boost | 12 V | 2.5 A |
| D42V55F12 | Buck | 12 V | 4.5 A |
| D24V150F12 | Buck | 12 V | 15 A |
| U3V16F12 | Boost | 12 V | — |
Technical specifications
| Product | 12V Step-Up Voltage Regulator U3V40F12 |
|---|---|
| Brand | Pololu |
| Model | U3V40F12 |
| Category | DC-DC Step-Up Regulator |
| Topology | Step-Up (Boost) |
| Output Voltage | 12 V |
| Support | Official Pololu product search and support resources linked below |
Official resources
Find this product on Pololu | Pololu support and resources
What’s in the box
1 × 12V Step-Up Voltage Regulator U3V40F12
Frequently Asked Questions
Can I power a microcontroller with this?
Yes, if the regulator’s output voltage and current match your controller and all attached loads.
Yes, if the regulator’s output voltage and current match your controller and all attached loads.
Will it run cool at full load?
It depends on input voltage, airflow, and load current. Check thermal limits in the official Pololu resources.
It depends on input voltage, airflow, and load current. Check thermal limits in the official Pololu resources.
Is this better than a linear regulator?
For many builds, yes. Switching regulators are usually more efficient and waste less heat.
For many builds, yes. Switching regulators are usually more efficient and waste less heat.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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